I hae found a problem. Exporting products to CSV works fine. I must import the CSV file into excel using UTF-8 encoding, or the data are not readable. That's no problem. But there is a roblem in importing prices. As soon as the prices are higher than 11.59, they are imported as dates - e.g. 12.50 is imported as dec.50. How to solve this?
I have found a way. I think, however, that all steps, I had to do, should be mage on e-shop site. 1. Export from the e-shop is simple. Result - *.csv file - is safely saved on admin's PC. 2. The import shall be made on new empty spreadsheet in excell. 3. Mandatory is: a) import as CSV b) encoding UTF-8 c) delimiter $ (all other delimiters shall be unchecked d) data format - general (for column "Price") e) Advanced: Decimal separator - replace "," to "." - depends on OS International System Settings - check, if all prices are importer correctly.